Pumping mechanism



May 29, 1945 1 J.'w.- HATCH 2,376,856

' I PUMPING MECHANISM Filed March 3, 1942 3 Shee ts-Sheet 1 INVENTOR.

JAM S W. H TcH BY I 7 1 HIS AhENEY y 1945? I J. w. HATCH 2,376,856 I PUMPING MECHANISM Filed March 3, i942 3isheet'sshe et'2" INVENTORY.

, I Mes w HATCH Q 0 v HIS ATTOENEY May 29, 1945. J. w. HATCH.

PUMPING MECHANISM :s Sheets-Sheet 3' Filed March 5, 1942 a 7 N m w 1 x W W U Ill]..- T N MM F r m E Km. r hn O p Y 5 ,w .w 5.; M 1 an 5 m 7 Mai M/m 4 M /1\./ w u Ir WI II Ill! 1 u W HH H MM E uwJmu m m l 4!!! IHHIWLWIW' ll 1 HIIHHHH Patented May 29. 1945 UNITED STATE s PATENT OFFICE PUMPING MECHANISM James W. Hatch, Detroit, Mich, assignor of onehall to Follxe E. Sandeil, Detroit, Mich.

Application March 3, 1942. Serial No. 433,135

' 34 Claims. (01. ins-'41) My invention relates to a new and useful improvement in a pump mechanism and particuliquid is pumped to the injection nozzles.

In a pumping mechanism of this class it is also desirable, when injecting volatile fuels, that the beginning of the injection be controllable while the termination of the injection remains constant with the throttling being accomplished by changing the starting of the injection and therebylengthening or shortening the duration of the injection, it is an object of the .present invention to provide a structure whereby this may be accomplished.

. It is another object of the invention to provide a pumping mechanism of this class whereof a novel mechanism for controlling the delivery of the fluid from the pump cylinder wherein the end point of the delivery remains constant and the beginning of the delivery may be variably controlled.

Another object of the invention is a provision o a novel means whereby the fuel delivered from each pump cylinder of a multiple'fuel injection unit may be adjusted for assuring equal volumetric displacementof the cylinders.

Another object of the invention is the provision of a pumping mechanism whereby the excess amount of fuel pumped is circulated thru the pumping unit for heat transfer purposes.

. ther objects may appear hereinafter.

It is recognized that various improvements or changes may be made in the detail of, the structure illustrated without departing from the spi it of the invention, and it isintended that such v riations and modifications shall be em- It is Fig. 1 is a longitudinal central sectional view of the invention taken on substantially line l---I of Fig. 2.

Fig. 2 is a transverse sectional view of the invention taken on substantially line 2-2 of Fig. 1.

Fig. 3 is a fragmentary sectional view taken on line 3-3 of Fig. 2.

Fig. 4 is a longitudinal sectional view of a 1 pump cylinder showing one position of operation.

.Fig. 5 is a view similar to Fig. 4. showing another position of operation.

Fig. 6 is a view similar to Fig. 5 showing another position of operation.

Fig. 7 is a view to ,Fig. 6 showing another position of operation.

Fig. 8 is a view similar to Fig. .7 showing an- 1 other position of operation.

braced within the scope of the claims which form a part hereof.

Incorporated and made a part of this specification are drawings in which Fig. 9 is a view similar to Fig. 8 showing another position of operation.

Fig. 10 is a view similar to Fig. 9 another position of operation.

showing Fig. 11 is a fragmentary sectional view showing a slightly modified form of plunger.

Asshown in Fig. l the invention comprises a housing IQ-secured to which is an end plate or head 20 by means of the bolts 2|, lugs 22 projecting outwardly from this housing for the reception of securing meanswhereby the housing may be fixedly attached to a stationary supporting body. A plurality of axially directed passages which serve ascylinders are formed in the housing. In each of these passages, adjoining one end thereof, is slideably mounted a tappet or guide sleeve 24, having a head 25, in which is formed a spherical surface 26, substantially semi-spherical in contour. A cylinder 21 is provided for a piston 28 which is slideably mounted therein. Projected downwardly from this piston 28 is a push rod 29 provided with a collar 30 upon which rests a washer 3| against which bears one end of a. spring 32, the other end hearing against the washer 33 fixedly mounted in passage 23. A pin 3 projectsfrom the end of rod 29 and extends thru a substantially semispherical shoe 35 which is positioned in the spherical surface 26. Embracing this pin is a spring 36 .which serves to normally resist rocking movement of the shoe 3! and tends to maintain the shoe 35 aligned with the push rod 29..

Threaded to the lower end of the housing 19 is a retaining ring 31 which serves to engage and retain in position the swash plate or actuating 7 which are engaged a rotating driving bar. the construction being such that as the swash plate 88 is rotated, the piston 28 will be forced upwardly 1 positively and returned by the action of the spring i Thus there is afiorded a means for recipro cating the piston 28.

The piston 28 is provided with a threaded socket 4| into which is threaded a depending portion 42 of a control plunger 43 which may be termed 1 a bleed passage bearing member. This plunger 43 is provided with the axial passage 44 opening 3 into the diametrically extending passage 45 so as i to communicate with chamber as beneath the 1 bushing 41 or guide sleeve. This Ibushing is held in position by the ring 48. Where the passages f 45 open into chamber 46 the control plunger or piston 43 is cut away on its periphery to proi vide a chamber forming groove 49. The chamber 46 communicates thru the opening 50 with the chamber 5| in the housing It. a

Formed on the housing l9 at spaced intervals 3 are the bosses 55, in each of which is formed a I j cavity 56 for reception of a spring pressed check 3 valve 58. This check valve controls communica- 1 tion of passage 51 with cavity 56. Leading from .1 the cavity 56-is the outlet passage 59 closed at its 'lower'end by the plug 60 and having the lateral extension 6| communicating with the ,bore 62 formed'in the lug 22, thisbore 62 being suitably 5 connected in communication with, the injection 1 nozzle, which is not shown, and which, of itself, forms no part of the present invention. V

The construction is such that as the swash plate 38 is rotated the control plunger 43 is reciprocated. As the piston 28 moves upwardly the regulate the amount of liquid which is delivered at each impulse to the injection nozzle.

A peripheral groove 12 is formed on the piston I 26 communicating with which is a plurality of axial passages 13 formed in this piston 28 which communicate with the chamber 46. Formed in the inner surface of cylinder 21 at the location of the openings 58 and 50' is the groove 82 communicating with chamber 5| and 52.. As the piston 28 moves upwardly as shown in Fig. 4 fluid is forced from chamber 46 through the groove 82 and openings 56 and 50 into chambers 52 and 5| and will likewise flow thru'the groove 49, openlugs and 44 into chamber 5!. As the piston 28 reaches the position shown in Fig. 5 chamber 46 communicates with chamber 5| only through the groove 49, openings 45 and 44. As the piston 28 moves upwardly from the position in Fig. 5

gaseous formations will be forced from chamber 46 to chamber, 5| since the groove 49 communicates with chamber 46 at the highest point in chamber 46 when cut-ofi'occurs. Asthe Diston 28 reaches the position shown in Fig. 6 injection begins and continues until the spill groove 12 on piston 28 communicates with groove .82 in cylinder 2'! as shown in Fig. 7 at. which time injection ends, since communication is established between chamber 45 and chambers 5| and 52 through openings 13, spill groove 12, groove 82 and openings 50' and 54.

As the piston 28 continues past top center and starts its downward travel as illustrated in Fig. 8

1 volume of the chamber 46 is reduced and the openings 50 and 50 are gradually closed and the Q liquid and gaseous formations in the chamber 46 3 are forced outwardly thru the passage 44 where they may fill the chamber 5| and the space above it from which they will leak under gentle pressure through the outlet nipple 63 which is connected either back 'to the source of supply or to a suitable vapor eliminator, said liquid carrying heat and gaseous formations with it. As the control j plunger 43 moves into the bushing or guide sleeve 4? so that the lower edge of the groove 49 cuts 01f communication of the openings 45 with the chamber 46 the continued upward movement of the piston '28 will force the liquid outwardly thru the passage 51 into the cavity 56, from which it chamber 46 may beyaried. As the member 43 is threaded inwardly of the socket 4| the piston 28 will'move upwardly a predetermined distance into chamber. 46 before the-openings, ar closed by the bushing 41, thus reducing the volume which would be delivered to the cavity 56. As Q the regulating plunger 43 is threaded in the opposite direction, the volume vof liquid delivered to the cavity 56 would be accordingly increased.

f Thus it becomes possible by this adjustment to 15 ber 43 inwardl or outwardly of the socket 4|, I

the groove "49 on the control plunger 43 communicates with chamber 46 as shown in Fig. 9 at which time communication is established between chamber 5| and chamber 46 through the openings 44 and 45, and groove 49. As the piston 28 continues farther on its down travel as shown in Fig. 10 communication is also established from chamber 5| tofchamber 45 through opening 50 and groove 82 as likewise through the opening 56' and groove 82' with chamber 52.

It is obvious that when injection begins, as shown in Fig. 6 a large area of fluid around groove 49 on control plunger 43 is substantially shut off from communicating with chamber 46 and at this point t e injection starts as shown by the arrows inthe opening 51 in Fig. 6. This would effect a beginning of injection on a closely defined point the groove 82 which provides a large free com munication from chamber 46 tochambers 5| and 52 as previously described. This structure and method of starting and finishing injection assures a sharp, well defined start and termination of the injection, and assures complete atomization of the fluid at the injection nozzle.

It is obvious from Fig. 1 that the control plunger 43 may be selectively adjusted in relation a to control member 66 by means of their toothed and assures equal displacement of all the cylinengagement. This adjustment provides a means of setting control plungers 43 in relation to pistons 28 in a multiple cylinder fuel injection unit unit is assembled.

In order to effect the threading of the memplunger 43.

described. I

A pinion 64 is fixedly mounted on the. upper end of plunger 43. This pinion 64 meshes with the teeth of the internal gear 56. This internal gear is connected by the spring arms 61 to a hub 68 carried by shaft. 69 projecting centrally outwardly thru end plate or head 20. A splined portion is formed on the shaft 69 on which a suitable handle ll may be mounted. By moving the handle H the shaft 69 may be rotated for effecting a rotation of the pinion 64 and thus accomplishing the desired control.

A passage 14 for the escape of gases from the chamber 52 is provided, The presence of the liquid in the chamber 5| and the space above it serves to maintain the operating mechanism cool. This is further accomplished by the fins 16 which are mounted on the housing or the head or the end wall.

The threaded connection between the'members 43 and 28 is sufiiciently loose so that any mis-alignment between these members will be compensated for by the clearance in the threads. It will be noted that the upper portion of the push rod 29 is formed flat faced. .This fiat faced portion engages in a corresponding hole in washer 33 which is fixed in the cylinder 23 and thus rotation of the member 28 is prevented.

In Fig. 11 is shown a modification of the invention wherein a piston 28 is slidably mounted in the bore 21 of housing l9. Fixedly mounted in the bore 21 is the bushing 41' retained in its position by the lock nut 48. Slideably mounted in the bushing 41 is a control plunger 43 having a longitudinal'passage 44' communicating with a diametrically extending passage 45 extending through'sa'id control plunger and provides comsages-50 audio and a recessed groove 82 in the cylinder wall 21. Fixedly mounted on the upper end of control plunger 43' is a gear 64' meshing with a toothed rack or control member 66'. The construction is such that as-the piston 28 is reciprocated, the control plunger43 reciprocates substantially in unison. At the position where the control plunger 43' engages with piston 28', l

a radial clearance is provided so that any misalignment of one member with the other istaken up by this clearance.

It is obvious that as the control member 66' is axially displaced, the control. plunger'43' is rethe amount of liquid that is delivered from chamber 46' at each impulse to the injection nozzle.

It is obvious also that the control plunger 41' and the piston 28' could be made integral in which case the piston 28' would not be restrained from rotational displacement.

It is, of course, believed obvious that as the member 28 moves inwardly the pressure developed on the fuel in the compression chamber 46 is insufficient to move the check valve-58 off of its seat until, after the openings 50 and 50' have been closed and the bleed passage opening 45 is also closed against communication with compression chamber 45.

What I claim as new is:

1. A fuel injection pump comprising: a com pression chamber for the reception of fuel fluid and having an inlet opening and an outlet opening; a reciprocating plunger slideable into said compression chamber for reducing the cubical contents thereof and forcing liquid therefrom. the location of said inlet openingv being such that said plunger will close the same upon its initial entrance into said chamber; a cylinder spaced from and in axial alignment with said plunger; a bleed-passage-bearing member carried by said plunger and engageable in said cylinder and having a bleed passage therein communicating with said chamber for bleeding fluid therefrom. the movement of said plunger into the said chamber a pre-determined distance effecting a, movement of said bleed member. into said. cylinder suflicient ly for enclosing said bleed passage therein and closing communication of said bleed passage with said chamber; a relief passage carried by said plunger for, upon movement of said plunger into said chamber a pre-determined distance, relieving the pressure on the fluid being forced outwardly of said chamber.

2. A fuel injection pump comprisingz a compression chamber for the reception of fuel fluid and having an inlet opening and an outlet opening; a reciprocating plunger slideable into said tationally displaced in relation to plunger 28' and bushing 41'. The lower face of the bushing 41' is provided with an irregular surface 81. For purposes of illustration, this surface 81 is a straight surface on an angle to the axis of said control It is obvious that by rotating, plunger 43' relative to the bushing 41', that the point of cut-off of communicationbetween chamber .46. and 5| through the passage 48' and 44' may be varied by the angular surface 81 and the passage as the said control'plunger 43' is recompression chamber 'for reducing the cubical contents thereof and forcing liquid therefrom, the l location of said inlet opening being such that said plunger will close the same upon its initial v entrance into saidchamber; a cylinder spaced from said plunger; a bleed-passage-bearing member carried by said plunger and engageable in -said cylinder and having a bleed passage therein .said chamber a pre-determined distance, establishingcommunication of said outlet opening with the exterior of said chamber and relieving the pressure on the fluid being expelled thru said outlet opening.

3. A fuel injection pump comprising: a compression chamber for the reception of fuel fluid and having an inlet opening and an outlet opening; a reciprocating plungr slideable into said compression chamber for reducing the cubical contents thereof and forcing liquid therefrom, the location of said inlet opening being such that said plunger will close-the same uponits initial entrance into said chamber; a cylinder spaced from said plunger and in substantial axial alignment therewith; a. bleed passage-bearing memkm carried by said plunger and slideably engaging in said cylinder'and having a bleed passage therein communicating with said chamber for bleeding fluid therefrom, the movement of said plunger into the said chamber a pre-determined distance efiecting a movement of said bleed member into said cylinder suflilciently for enclosing,

said bleed passage therein and closing communi-= cation of. said bleed passage with said.chamber;

and means for adjusting the relative position of said bleed-passage-bearing member and said plunger for varying the position of the inward movement of said plunger into said chamber at which the communication of said bleed passage with said chamber is dis-established; a relief pasi sage carried by said plunger for, upon movement asvaeoe I n 1 pinion for adjusting the relative position of the I bleed mechanism toits plunger.

'7. 'In a fuelinjector of the class described a;

housing having a plurality of liquid receiving chambers formed therein, each provided with in- .let and outlet openings, each'of said chambers, while in communication with the inlet openings being, in communication with a chamber in the interior of said housing and a bleed mechanism tioned-charnber. n 8. In a fuel injector of the class described a housing having a plurality of liquid receiving compression chamber for reducing the cubical contentsthereof and forcing liquid therefrom, the location of said inlet opening being such that said plunger will close the same upon its initial entrance into said chamber; a cylinder spaced 3 from and in substantial axial alignment with said plunger; a bleed-passage-bearing member car ried by said plunger and slideably engaging in said cylinder and having .a bleed'passage therein communicating with said chamber for bleeding fluid therefrom, the movement of said plunger into the said chamber a pre-determined distance effecting a movement of said'bleed-passage-bear ing member into'said cylinder sufliciently for enclosing said bleed passage therein and closing communication of said bleed passage with said chamber; and means for adjusting the relative position of said bleed-passage-bearing member and said plunger forvarying the position of' the inward movement of said plunger into said chamber at which the communication of said bleed passage with said chamber is dis-established; and means for, uponmovement of said plunger inwardly of said chamber a predetermined distance, establishing communication ofsaid outlet opening withthe exterior of said chamber and relieving the pressure on the fluid being expelled thru said outlet opening.

5. A fuel injection mechanism of the class described comprising a fuel receiving chamber have ing an inlet opening and an outlet opening, a plunger slideably projectable into said chamber for closing its inlet opening and forcing fluid.

forcibly from an outlet opening; a bleed-passagebearing member movable in unison with said plunger for bleeding fuel from said chamber through the bleed passage; andmeans for closing said bleed passage upon movement of said plunger into said chambera predetermined distance; and,

1 means for adjusting the relative position of said 1 bleed passage bearing member to said plunger for opening and forcing liquid outwardly thru an out-j let opening; a bleed mechanism associated with each of said plungers for bleeding liquid from the chamber; a pinion associated with each of said bleed mechanisms; and means operative on said" chambers formed therein provided with inlet and outlet openings, each of said chambers while in communication with the inlet opening being in communication with achamber in the interior of said housing, and a bleed mechanism for bleeding liquid from said first-mentioned chambers outwardly into the said second-mentioned chamber; and means for venting gases having formed in second-mentioned chamber.

9. In a fuel injector of the class described a housing having a plurality of liquid receiving chambers formed therein provided with inlet and outlet openings, each of said chambers; while in communication with the inlet openings, being in communication with a chamber in the interior of said housing, and a bleed mechanism for bleeding liquid from said first mentioned chambers second-named chamber; a third chamber in the interior of said housing communicating with said first-named chamber; and an outlet conduit com- .muni cating with said third named chamber.

11. In amechanism of the class described a plurality of liquid receiving compression chambers each having inlet and outlet openings; a plunger projectable into each of said chambers for closing the inlet opening and forcing liquid outwardly thru an outlet opening; a bleed mechanism associated with and movable in unison witheach of said plungers;jmeans for adjusting each of said bleed mechanisms individually relatively to its plunger for controlling the amount of liquid ejected from the compression chamber at a single .operation; and means for simultaneously adjusting a plurality of said 'bleed mechanisms to their plungers for'effecting relative re-location of said bleed mechanisms to said plungers.

12. A fuel injection mechanism of the class described comprising: a fuel receiving chamber having an inlet opening and an outletopening; a

plunger slideably projectable into said chamber for closing its inlet openingand forcing fluid forcibly from said outlet opening; a bleed-passage-bearing member connected to and moveable in unison with said plunger for bleeding fuel from said chamber through a bleed passage; and means for closing said bleed passage upon moveme'nt of said plunger into said chamber a predetermined distance; and means for adjusting relative position of said bleed-passage-bearing member to said'plunger for varying the extent of movement of said plunger at .which said bleed passage is closed; and means for preventing rctationof said plunger.

' a bleed mechanism, having a bleed passage, and

reciprocating in each of said chambers for closing said inlet openings and forcing liquid from said outlet openings; a bleed-passage-bearing' member carried by each of said plungers for bleeding liquid from said chambers through the bleed passage; means for closing said bleed passages upon movement of said plungers into said chambers a pre-determined distance; means for adjusting the relative positions of said bleedpassage-bearing members to said plungers for varying the extent of movement of said plungers at which said bleed passages are closed; means for adjusting said bleed members; and means for preventing rotation of said plungers.

15. In a pumping mechanism of the class described; a plurality of liquid receiving chambers, each having inlet and outlet openings; a reciprocating plunger projectable into each of said chambers and closing an inlet opening and forcing liquid outwardly through an outlet opening; a bleed mechanism associated with each of said plungers and provided with a bleed passage for bleeding liquid from the chamber into which said plunger projects; means for closing said bleed passage upon projection of said plunger into said chamber a predetermined distance; a pinion associated with each of said bleed mechanisms; means operative on said pinionsfor adjusting the relative positions of the bleed mechanism to its plunger; and means for reciprocating said plungers. g.

16. A fuel injection pump comprising; acylinder having a compression chamber provided with inlet and outlet openings; a smaller cylinder extending beyond said chamber; a plunger slideable into said chamber; a bleed member yieldably engaged with said plunger and having a bleed passage communicating with said chamber and" smaller cylinder to close said bleed passage at a adjustably engaged with said plunger and having a bleed passage communicating with said cham bar and slideable into said reduced cylinder to close said bleed passage at a predetermined position of said plunger; and means to prevent rotation of said plunger.

19. A fuel injection pump comprising; a cylinder having a compression chamber provided with inlet and outlet openings; a reduced cylinder extending beyond said chamber; a plunger slideable into said chamber and having a relief passage adapted to establish communication between said chamber'and said inlet opening at a predetermined position of said plunger; a bleed member adjustably engaged with said plunger and having a bleed passage communicatingwitfisaidchmnber and slideable into said reduced cylinder to close said bleed passage at a predetermined posi: tion of said plunger; and means to prevent rotation of said plunger.

20. A fuel injection pump comprising; a cylinder having a compression chamber provided with able into said chamber to close said inlet opening and to provide pumping effect; said plunger having a relief passage adapted to establish communication between said chamber and said inlet opening at a predetermined position of said plunger; an adjustable bleed member carried by said plunger and having a bleed passage commu-, nicating with said chamber and slideable into said predetermined position of said plunger; and means to prevent rotation of said plunger.

' 21. A fuel injection pump comprising; a cylinder having a compression chamber provided with 0 inlet and outlet openings; 9, reduced cylinder exslideable into said smaller cylinder to close said bleed passage at a predetermined position of said plunger.

17. A fuel injection pump comprising; a cylinder having a compression chamber provided with inlet and outlet openings; a smallercylinder extending beyond said chamber; a plunger slid'eable into said chamber to close said inlet opening her and slideable into said smaller cylinder to tion oi. said plunger. 1

18. A fuel injection pump comprising; a cylinclose said bleed passage at a predetermined posider having a compression chamber provided with inlet and outlet openings; a reduced cylinder extending beyond said chamber; a plunger recipro tending beyond said chamber; a plunger slideable into said chamber; a bleed member adjustsaid chamber to close said inlet port and to provide pumping effect; an adjustable bleed member carried by said plunger and having a bleed passage communicating with said chamber andslideable into said smaller cylinder to close said passage at a predetermined position of said plunger;

means to adjust said bleed member; and means to restrict rotation of said plunger.

23. A fuel injection pump comprising; 9. cylinder having a compression chamber provided with inlet and outlet ports; a reduced cylinder extending beyond said chamber; a plunger slideable into said chamber and having a relief passage adapted to establish communication between said chamber and said inletport at a predetermined position of said plunger; an. adjustable bleed member carried by said plunger and having a bleed passage communicating with'said chambet, and slideable into said reduced'cylinder toclose s'aid bleed passage at a predetermined position of said plunger; means to adjust said bleed member; and means to prevent rotation oi said plunger.

cative in said chamber to close said inlet opening and to provide pumpingei'fect; a bleed member inlet and outlet openings; a smaller cylinder ex- I tending beyond said chamber; a plunger slide- 7 24. Afuel injection pump comprising; a cylinder having a'compression chamber provided with inlet and outlet ports; a smaller extending cylinder beyond said chamber; a plunger slideable into said chamber to close said inlet port and to provide pumping effect; said plunger having a relief passage adapted to establish communication between said chamber and said inlet port at apredetermined position of said plunger;

an adjustable bleed member carried by said plunger and having a bleed passage communicating with said chamber and slideable into said extending cylinder to close said bleed passage at a predetermined position of said plunger;

means to adjust said bleed member; and means to prevent rotation of said 'plunger.

25. A fuel injection mechanism of the class de- I scribed comprising a fuel receiving chamber, having inlet and outlet ports; a reduced cylinder extending beyond said chamber; a plunger reciprocative in said chamber to close said inlet port and to provide pumping efiect; a bleed-passage- --b'earingmember carried by said plunger and having a bleed passage communicating with said chamber, and slideable into said reduced cylinder to close said bleed passage at a predetermined position of said plunger; and means for adjusting the relative position of said bleed-passagebearing-member and said plunger for varying the extent of movement of said plunger-into said chamber at which the communication of said bleedpassage with said chamber is dis-estab- -lished.

----26. A fuel injection mechanism of the class described comprising a fuel receiving chamber having inlet and outlet ports; a cylinder extend= extending beyond said chamber; a plunger slideable into said chamber; a bleed member adjustably engaged with said plunger and having a bleed passage communicating with said chamber and slideable into said smaller cylinder to close said bleed passage at a redetermined position of said plunger; means to rotationally adjust said bleed member relative to said plunger; and means to preventrotation of said plunger.

30. A fuel injection pump comprising; a cylinder having a-compression chamber provided with inlet and outlet openings; a smaller'cylinder extending beyond said chamber; a plunger slideable into said chamber; a bleed member axially adjustably engaged with said plunger and having a bleed passage communicating with said chamber .and'slideable into said smaller cylinder to close said bleed passage at a predetermined position of said plunger; means for rotating said bleed member for efiecting said axial adjustment; and means to prevent rotation of said plunger.

31. A fuel injection mechanism of the class described comprising a fuel receiving chamber having inlet and outlet ports; a cylinder extending beyond said chamber; a plunger slideable into said chamber to close said inlet port and to force fuel from said outlet port; a bleed-passage-bearf ing member engaged with said plunger and provided with a peripheral relieved portion commuing beyond said chamber; a plunger slideable into said chamber to close said inlet port and to force fuel fromsaid outlet port; a bleed-passage-bearing-member, adjustably engaged with said nicating with said passage, and guided in said cyl-.

inder for closing said passage upon movement of Jsaid plunger into said chamber a predetermined distance; means to adjust said bleed member;

and means to prevent rotation of said plunger. 32. A fuel injection pump comprising; a cyl-- inder having a compression chamber provided with inlet and outlet openings; a smaller cylinder extending beyond said chamber; a plunger slideable into said chamber; a bleed member adjust- 0 ably engaged with said plunger'and having a plunger and provided with a peripheral relieved 7 said plunger; means to axially adjust said bleed member relative to said plunger; and means to prevent rotation of said plunger.

28. A fuel injection pump comprising; a cylinder having a compression chamber provided with inlet and outlet openings; a smaller cylinder extending beyond said chamber; a plunger slideable into said chamber; a bleed member adjustably engaged with said plunger and having a, bleed passage communicating with said chamber and-slideable into said smaller cylinder to close said bleed passage at a predetermined position of said plunger; means to rotationally adjust said bleed member.

29..A fuel injection comprising; 9. cylinder having a compression chamber provided with inlet and outlet openings; a smaller cylinder bleed passage communicating with-said chamber and slideable into said smaller cylinder to close said bleed passage at a predetermined position of said plunger; and means to adjust the axial relationship of said plunger and said bleed member.

33. A fuel injection pump comprising; a cylinder having a compression chamber provided with inlet and outlet'openings; a smaller cylinder extending beyond said chamber; a plunger slideable into said chamber; a bleed member adjustably engaged with said plunger and having a bleed passage communicating with said chamber and slideable into said smaller cylinder to close said bleed passage at a predetermined position or said plunger; and means to adjust the rotational relationship of said plunger and said bleed member. a

34. A fuel injection pump comprising; a cylinder having a compression chamber provided with inlet and outlet openings; a smaller cylinder extending beyond said chamber; a plunger slideable into said chamber; a bleed member adjustably engaged with said plunger and having a bleed passage communicating with said chamber and slideable into said smaller cylinder to close said bleed passage at a predetermined position of said plunger; and means to adjust the rotational relationship of said bleed member and said smaller cylinder.

JAMEsw. HATCH." 

